AIDS has been a leading cause of death among Latino women and men 25 to 44 years of age for more than a decade. The few HIV prevention and treatment interventions developed specifically for Latino men have focused on injecting drug users (IDU) or men who have sex with men (MSM), but have neglected a critical epidemiological group, men who have sex with men and with women (MSMW). This group is particularly relevant in understanding the spread of HIV given the role they play in sexual network connections between the homosexually active male population and heterosexual population. The proposed study will develop an innovative pilot intervention for behaviorally bisexual Latino men. We propose the following specific aims: 1) To describe the mechanisms by which contextual factors of labor and cultural backgrounds (such as access to employment, ethnic-racial tensions, coping with job-related situations, heterosexism and gender norms in the workplace) influence bisexual men's likelihood of engaging in risky sexual practices;2)To explore how men's notions of power are shaped by the centrality of family and religious background, and how these factors in turn, facilitate or prevent sexual risk taking among bisexual Latino men;3) To describe bisexual Latino men's ideologies of HIV risk, the geographical context of HIV risk, and how bisexual risk behavior, and how they are related or not to gender and power dynamics in the men's lives;and, 4) To examine how the perceptions of members of AIDS Service Delivery Organizations (ASDOs) of societal notions of Latino masculinity and bisexuality create or limit access to HIV prevention services for bisexual Latino men in the New York Metropolitan Area. To accomplish these aims, we propose a 4-year ethnographic study design with two components of data collection. The first component will consists of in-depth interviews with behaviorally bisexual Latino men (n=160) from five research sites in the New York City metropolitan area. The first two years of the study will be dedicated to the in-depth interviews component. The second data collection component of the study will be an ethnography. This component will last 3 years, beginning in years 1 and 2 with key informant interviews (n=25) and continuing in year 3 with ethnographic mapping and 25 group interviews with AIDS Service Delivery Organizations across the 5 research sites. The last year of the project will focus on using Intervention Mapping (IM) to analyze the data collected and design the pilot intervention to reduce HIV risk among bisexual Latino men. The proposed study will be one of the first large-scale research projects to focus on issues of bisexuality and HIV risk among Latinos in the United States. PUBLIC HEALTH RELEVANCE: 1. Given the raise in HIV cases in the United States, particularly among homosexually and bisexually active men of color, this study takes an innovative approach to the examination of HIV risk among by exploring how broad forms of social inequality and the sexual ecology of bisexual behavior among Latino men constrain the options for a relatively less powerful group of men, and how ideologies of masculinity intersect with structural social inequalities to create HIV risks for bisexual Latino men. 2. This will be one of the first large-scale research projects to focus on issues of bisexuality and HIV risk among Latinos and the first one to examine how the context of labor and sexual markets shape the sexual lives and health risks of bisexual men of color. 3. The proposed study will be one of the few research projects that utilize HIV prevention research to design a multilevel, theory and evidence-based intervention to reduce HIV/STI risk for bisexual Latino men, a consistently overlooked population in public health.